Tannic acid fermentation. I. Tannic acid fermentation. II Effect of nutrition on the production of the enzyme tannase ...

During 1907-1908, a preliminary investigation of the conditions of tannic fermentation was made by the writer with the purpose of improving the practical methods involved.In the course of this preliminary investigation a number of interesting observations were made, justifyi further study of the conditions of the fermentation and of the relation of various organisms to the process.With the progress of the investigation other phases suggested themselves, until ultimately four distinct but correlated parts of the subject were experimentally studied.Part I, here reported, includes chiefly: (1) the toxicity of tannic acid for various fungi; (2) a comparison of the organism Aspergillus niger and Penicillium sp. in the fermentation of tannic acid; (3) the conditions and influence of various factors on the fermentation process.Part II is concerned primarily with the influence of nutrition on the production of the enzyme tannase, and will be reported in a subsequent paper.These investigations were begun at the suggestion of Prof. B. M. Duggar and prosecuted in his laboratory.It is a pleasure here to express my thanks for the advice, kindly criticism and assistance, which he has so generously given. II. INTRODUCTION.Chemical nature of tannic acid.Wagner! has grouped the tannins into a 'physiological' and a "pathological'' series, the latter including, as most important, the tannin of oak galls as 1R.Wagner: Beitrage zur Kenntnis und zur quantitativen Bestimmung